Improve tools.metric module
Improve tools.metric module

SpaceAppsXploration/grab,DDShadoww/grab,kevinlondon/grab,maurobaraldi/grab,giserh/grab,kevinlondon/grab,codevlabs/grab,codevlabs/grab,liorvh/grab,raybuhr/grab,lorien/grab,alihalabyah/grab,pombredanne/grab-1,liorvh/grab,SpaceAppsXploration/grab,DDShadoww/grab,subeax/grab,subeax/grab,raybuhr/grab,lorien/grab,istinspring/grab,huiyi1990/grab,giserh/grab,istinspring/grab,shaunstanislaus/grab,huiyi1990/grab,shaunstanislaus/grab,pombredanne/grab-1,subeax/grab,maurobaraldi/grab,alihalabyah/grab